Omega Owners Forum
Omega Help Area => Omega General Help => Topic started by: Gibbo486 on 20 February 2013, 12:58:30
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Hi
I am new to this club and sincere apologies if this issue has been raises before. I have looked at the various topics but couldn't find one relating to this issue.
I have just bought (or on the process of buying) my mates 2001 Y reg omega 2.6 v6 CDX saloon. It's just done 85k miles. He bought it 18 months ago and has had 22k relatively trouble free motoring with it.
He said that the coolant needed topping up every 4-6 weeks but it was only minimal and he couldn't see any leaks and I can't either.
A couple of months ago the engine management light came on and he said it was running irregularly on idle so he had a diagnostic check done and they said it was the air flow meter. He had that replaced and all seemed well. A couple of weeks later the engine management light came back on again but it was running ok apart from occasionally it would just cut out when going to idle after driving.
Since I have had it for last couple of weeks I have noticed that the car runs ok when on motorway and temp is sticking at normal (around 85) but when it is dark I have noticed smoke coming from my car showing in the headlights of cars behind but I can't see smoke during daylight hours. That said when I get to my destination after a longish motorway journey (30 miles) the car runs really rough at tick over and cuts out a lot and quite a bit of smoke from exhaust. A greyish colour
When I get in it later and start it, it starts on the button and again goes well on motorway although lumpy on tickover. I have noticed a fair bit of mayo on oil filler cap and neck of filler spout on the inside but no trace of any on the dipstick.
Could the management light mean a problem with another sensor and would it cause problems as discussed.
Apologies for long winded explanation and any advice/recommendations would be gratefully received
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Hello and Welcome :)
First thing to do is the "pedal trick" to get the codes... no other action required yet .. as it would all be guesswork !!
http://www.omegaowners.com/forum/index.php?topic=90581.0
have a go at that then tell us the results and we'll move on from there .. random diagnostics followed by random part changing = waste of time ... lets attack the problem in a logical manner :)
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Welcome to OOF.
As Entwood says. First thing is to read the codes engine codes as the link.
Read the codes and post them up. Probably misfires caused by oil leaks from old cam covers filling the plug wells. Cam covers gaskets are a service item on these almost.
But read the codes first, see what's upset it. :y
Was it a genuine maf ?
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Hi
Many thanks to you both for a quick reply. Have done the accelerator test and it gave two sets of codes as shown below
10 1 7 3
10 1 7 10
Is that good or bad news ?
Thanks once again guys
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Decode can be found here for future reference ..
http://www.omegaowners.com/forum/index.php?topic=90594.0
P0170 Fuel trim malfunction (Bank 1)
P0173 Fuel trim malfunction (Bank 2)
These codes mean that the fuel mixture is weak/rich on both Bank 1 and Bank 2 this is often caused by an intake air leak or sensor fault such as throttle position sensor or air mass metering.
Intake leak ... check by spraying around LIGHTLY with carb cleaner whilst the engine is running, if the engine note suddenly changes you have found the leak as the cleaner is sucked in and burned as unmetered fuel
Throttle position sensor can be cleaned I believe although I've not done it myself
Air mass meter also called the Mass Air Flow (MAF) sensor you have recently replaced ... was it a genuine vauxhall item as pattern ones may fail early ?? (as Chris intimated .. :) )
HTH :)
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Guessing pattern maf. Bosch only. Search the part no. It's used on a few vehicles.
Or a breakers here might help.
Check for air leaks in the inlet first though, just to be safe. :y
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Thanks guys and thanks for the link.
Looking at the receipt for the diagnostic check and replacement maf it doesn't actually say. The total bill was £190 and the maf was £63 but I suppose that means nothing. Will get some spray as you suggest and try the leak test and get back to you.
Can't thank you enough for your help thus far
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Just had a look at what I think is the maf and it has Bosch on the pipe that the wire block goes in to
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The sensor itself sits within the pipe - possible that new sensor swapped into original pipe and may be pattern
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You are probably right. I looked again and sensor part is shiny and black but pipe is dirty
I looked on ebay and see that fault code readers and resetters are only about £15. Would it be worth getting one of these or will that only throw up the same codes. I'm not brilliant with cars and need mine to get to Heathrow and back every day and was wondering if it would harm the engine much using it for a few days until i can discover what needs replacing
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You are probably right. I looked again and sensor part is shiny and black but pipe is dirty
I looked on ebay and see that fault code readers and resetters are only about £15. Would it be worth getting one of these or will that only throw up the same codes. I'm not brilliant with cars and need mine to get to Heathrow and back every day and was wondering if it would harm the engine much using it for a few days until i can discover what needs replacing
The codes you have will go as soon as the problem is rectified :)
The pedal trick reads exactly the same codes :)
ergo .. no external reader/resetter needed
It sometimes is worth unplugging the MAF (the fault light will stay on) and seeing if the car runs any better .. it often does .. so "proving" that the MAF is faulty ... new MAF then sorts things out .. :)
Worth a try ?? :)
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Tried that. As soon as I unplugged the maf it hardly ticked over and as soon as I plugged it back in it ran much better so I guess the maf is probably ok so back to the drawing board I guess.
At least that has eliminated one possible
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I spoke to my mate who had the maf replaced. He said the maf was replaced then within two days the fault light came on for a day or two then went off for about two weeks then came back on and stayed on and has been on for last 8 months but as car was running ok apart from occasional cutting out at idle he didn't bother
In light of that do you think it could still be a faulty maf. I did disconnect it but the car hardly ticked over and was very rough and ran better when I reconnected it
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I'd be interested in what the long term trims are. Plus the MAF readings.
Ever pass Brackley, Alton (Hampshire) or Nottingham?
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Is that brackley near Bicester ? I do visit relatives in redditch and go via A41 and m40. I'm at a loss by what you mean by trim etc
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At those locations are guys with "tech2" diagnostic kits who actually know how to use it .. and can use the kit to monitor "live data" whilst the engine is running... they can also test numerous other bits and bobs at the same time ...
Well worth it if you can get to one of them to diagnose odd problems .. :)
The ECU "learns" how much fuel the engine needs under most circumstances and sets a "long term fuel trim" to compensate .. sort of sets the mid position for the short term fuel trims to work around .. makes the response times/efficiency better ... with the tech2 these trims can be monitored whilst running, and a sensible diagnosis made .. :)
The MAF can also be watched to see exactly how mach air it "thinks" is reaching the engine .. as against how much air "should" be getting there !!
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please post when you get it sorted similar problems with my y26se lots of mayo in filler neck lumpy as hell foot to floor to start 200 max revs untill it dies grey smoke my petrol has turned into a very lumpy diesel :( got a mate popping round with code scanner fingers crossed!
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Hi Gibbo486 and welcome to the OOF! :y
You mentioned you travel to Heathrow frequently, in which case this link should come in extremely handy for spare parts!
Steve (the Owner) is a member here and a good bloke. Mention your OOF membership & you get a discount on your purchase! :y
http://www.google.co.uk/url?sa=t&rct=j&q=omegaspareparts&source=web&cd=1&cad=rja&sqi=2&ved=0CDoQFjAA&url=http%3A%2F%2Fwww.omegaspareparts.com%2F&ei=wZ80Uc3KI4bR0QXaroGABg&usg=AFQjCNGjCuQ42vl_ciasF5Vg3z80oqi19A&bvm=bv.43148975,d.d2k
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Hi Guys
How's it going with this problem Gibbo?
There's similarities with mine which is well documented elsewhere here.
I'm convinced my fuel trim codes aren't down to the MAF itself. But could be the result of a cross wire, lose connection or even excessive cooling when reaching 91 degrees.
I also get P0100 which is MAF heater circuit.
Got a MAF off Steve who assured me it came of a well running car....it didn't work.
Got a Chinese MAF from Autosensors on ebay...EML switched off imeadiately...then came back on after awhile. Got them to refund and send me another. Same thing happened.
Reset the codes, disconnect the battery over night...EML off but back on again. This is all the same with any of the 4 MAF's I now have.
Recently had the Chinese MAF's in...car going fine but...EML and codes back after making a sharp right hand turn with one in. Then with the other, car going well MPG improving all the time (but strangely only round town, not on a long run), then go up a road with evil speed bumps...EML and codes back after a particularly nasty bump.
Much to Kevin's dismay I tested all the MAF's with an Ohm meter...Standard Bosch MAF's had similar readings (which indicates that if nothing was wrong with my original MAF then the one I got of Steve was ok too...or both are bad and there's a different problem) and though completely different the Chinese MAF's had similar readings to each other. There is no change in any readings wether the EML and codes are registered or not.
Which tells me that as there is no change with any MAF how can the problem be the MAF sensor?
I recently had reason to start the car from cold and drive it straight away, rather than wait for it to warm up, whilst it was barely running i.e. the rough starting/no tick over but it drove...then YIKES at the 1st junction....no brakes!!!! indicating a vacum (i know spell check, I know) problem. When the rough starting stops and tick over is normal I have brakes. When warm tick over increases if I pump the brakes! Is this normal???
When I've been under the bonnet inspecting the rough starting/barely ticking over problem, I've heard a solenoid suddenly click and hey presto...ticks over sweetly. This solenoid sound comes from behind the Plenum.
I noticed that the coolant barely got above 80, so changed the thermostat...thanks OOF for the guidance. Has there ever been such a stupid design that puts so much work just in to changing a thermostat??? Crazy...poxy B bolt lol. I'm adapting my old housing to come up vertical and bend through the "V" behind the throttle body and then to the top of the rad.
Anyway, when filling up with coolant, I put so much in then ran the car to get warm with my fingers crossed (which actually worked this time...no leaks). Then as I was topping up the expansion tank the sound of the engine and tick over changed as the cold coolant was being taken in. Struck me as being a bit odd. What does anyone think???
Also, now the coolant is getting up to temperature the cooling fans are switching on. The problem is now the temperature yo yo's between 91 and 80. I've notice that the consumption on the MID drops after the 3 fans have been on and the temperature is 80-85. When it builds back up to 91, just before the fans come on the consumption doesn't drop and in fact gets better.
I've also not got the rough starting anymore from cold but do have it when the engine is warm. For instance after filling up with fuel or nipping in to Sainsburys then restarting the car. Is the something, a sensor of some kind that operate in higher or lower ambiant temperatures. When the weathers cold I get rough starting from cold but when it's only a few degrees warmer i.e. above 0, no rough starting from cold but rough starting when engine is warm?
Now 64,000 dollar question:-
Could the yo yo of the coolant temperature create a situation of confusion in the ECU and cause it to throw up fuel trim codes? I.E. when the coolant reaches 91 it feeds less fuel and when the coolant drops to 80 after the fans come on it feeds more fuel. This would cause havoc to the long term fuel trims surely and the codes disguise the real problem?
No. 64,001
Could a bad/lose connection that runs the MAF heater circuit throw up a P0100 code rather than the actual circuit within the MAF itself? As there is no change in the resistance in the MAF's I have. The ECU wouldn't know any different and just assumes it's at the MAF. Where on earth are the wires that connect to the MAF, specifically the MAF heater circuit, where do they go? Is there an earth for the MAF heater circuit or is it part of the general earthing of the car? I've noticed that the dash and MID alumination changes quite alot. Could a bad earth cause there to be too much volts in the circuit and confuse the ECU?
Sorry Guy's I know this is a long one but I'm as inquisitive as a child.
Cheers.
Dave
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You want to start it up and pull dipstick and if smokes your engine knackered-why say this?-missfires coolant loss and mayo in filler neck + smoke at front -sorry but you describing all symptoms same as mine=blown rings-excessive crankcase pressure-bet your rocker covers will leak next :y